1. Field of the Invention
The present invention relates to an array substrate, a method of manufacturing the array substrate and a liquid crystal display (LCD) apparatus having the array substrate. More particularly, the present invention relates to an array substrate capable of improving viewing angle and simplifying manufacturing process, a method of manufacturing the array substrate and an LCD apparatus having the array substrate.
2. Description of the Related Art
In general, a liquid crystal in an LCD apparatus varies an arrangement in response to an electric field applied thereto, and thus a light transmittance thereof may be altered. The liquid crystal is interposed between an array substrate having a thin film transistor (TFT) and a color filter substrate, and has an anisotropic dielectric constant.
The liquid crystal of the LCD apparatus is anisotropic so that an image display quality is dependent on the angle of a viewpoint. In a conventional LCD apparatus, the range of the viewpoint angle is restricted so that the image display quality is deteriorated. When the LCD apparatus is used as a monitor, the viewpoint angle may be more than 90°. The viewpoint angle having a contrast ratio of more than about 10:1 is defined as a viewing angle of the LCD apparatus. The contrast ratio is a ratio of a luminance of a dark image to a luminance of a bright image. When the LCD apparatus displays a darker image, and has more uniform luminance, the contrast ratio of the LCD apparatus increases.
The LCD apparatus may include a black matrix having a decreased reflectivity and use a normally black mode so as to prevent the leakage of a light and to display the darker image. When a voltage is not applied to a common electrode and a pixel electrode of the LCD apparatus having the normally black mode, a black image is displayed. In order to uniformize the luminance, the LCD apparatus includes a compensation film or a liquid crystal layer having a multi-domain. The liquid crystal layer having the multi-domain has a plurality of domains.
The LCD apparatus forming the multi-domain includes a mixed vertical alignment (MVA) mode, a patterned vertical alignment (PVA) mode, an in-plane switching (IPS) mode, etc.
When the LCD apparatus includes the MVA mode, a plurality of protrusions is formed on the color filter substrate and/or a thin film transistor (TFT) substrate to form the multi-domain, thereby increasing the viewing angle of the LCD apparatus. The protrusions are formed on the color filter substrate and/or the TFT substrate through additional processes, for example, such as coating process, photo process, etc., thereby increasing the manufacturing cost of the LCD apparatus. In addition, when the color filter substrate is misaligned with the TFT substrate, the protrusions may not form the multi-domain so that the yield of the LCD apparatus is decreased.
When the LCD apparatus includes the PVA mode, a plurality of slits is formed in the common electrode to distort the electric field in the liquid crystal layer to form the multi-domain, thereby increasing the viewing angle of the LCD apparatus. When the color filter substrate is misaligned with the TFT substrate, the slits may form a distorted multi-domain, thereby deteriorating the image display quality.
When the LCD apparatus includes the IPS mode, the TFT substrate includes a plurality of electrodes disposed substantially parallel with one another to form the distorted electric field. The LCD apparatus including the IPS mode, however, has decreased luminance.
In addition, the LCD apparatus forming the multi-domain is manufactured through the additional processes so that the manufacturing cost of the LCD apparatus is increased.